JP2012176548A - Method and apparatus for offset printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve printing accuracy when forming an electrode pattern (conductive pattern) on a substrate.SOLUTION: On a guide rail 2, a plate 3 and a printing object 5 are travellably provided, and a transfer mechanism section 17 is provided. In the transfer mechanism section 17, a blanket roll 10 is vertically movably provided, and a rotational angle detector 14 is provided for measuring a rotation angle. Further, a position detector 9 is provided for detecting moving positions of the plate 3 and the printing object 5. A synchronizing peripheral speed of the blanket roll 10 is obtained from a product of a synchronizing radius R between upper faces of the plate 3 and the printing object 5, and a rotational center O of the blanket roll 10, and an angular speed ω of the blanket roll 10 obtained based on the rotational angle measured by the rotational angle detector 14, and the synchronizing peripheral speed and a moving speed v of the plate 3 and the printing object 5 obtained based on a detection signal of the position detector 9 are synchronized from when the outer peripheral face of the blanket roll 10 is brought in contact with the upper faces of the plate 3 and the printing object 5 until transfer and retransfer of a printing pattern is completed.

Description

  The present invention relates to an offset printing method and apparatus used for performing fine printing with high printing accuracy on a printing target, as in the case of forming an electrode pattern (conductive pattern) on a substrate by printing.

  In the case where an electrode pattern such as a liquid crystal display is formed on a substrate to be printed, the electrode width is made as fine as, for example, about 10 μm, or the positional deviation when a plurality of electrode patterns are superimposed on the substrate, for example, In recent years, as an apparatus that satisfies this requirement, a printing technique that uses a conductive paste as a printing ink, for example, an offset printing apparatus that uses an intaglio offset printing technique, has been proposed. Has been proposed.

  As such an offset printing apparatus, for example, a guide rail extending in one direction is provided on the upper side of a horizontal base, and a flat plate and a printing target are placed on a moving table that can reciprocate along the guide rail. Are held at predetermined intervals, and a blanket roll is provided above the middle position of the guide rail in the longitudinal direction so as to straddle the guide rail.

  Accordingly, when the plate that has been inked in advance and the printing target are passed through the position immediately below the blanket roll as the moving table moves along the guide rail, the plate and the upper surface of the printing target are rotated. The printed blanket roll is brought into contact with a certain transfer printing pressure and a certain retransfer printing pressure in order from above to transfer a printing pattern from the inked plate to the outer peripheral surface of the blanket roll (acceptance). ) After performing the process, offset printing can be performed by performing a retransfer (printing) process of the print pattern from the outer peripheral surface of the blanket roll to the print target.

  By the way, in such an offset printing apparatus, when printing a fine print pattern with high printing accuracy, a print pattern transferred from a plate to a blanket roll and a print pattern retransferred from the blanket roll to a printing target There is a need to improve reproducibility. For this reason, it is necessary to improve the trajectory reproducibility of the plate or the moving table holding the printing object, and as a means for that, the unit of the portion in contact with the plate or the printing object on the outer peripheral surface of the blanket roll Synchronize (match) the speed (circumferential speed) obtained as the amount of circumferential movement per time with the speed (movement speed) obtained as the amount of movement per unit time of the plate or the printing target that contacts the blanket roll. Has been considered.

  As an offset printing apparatus provided with such means, conventionally, a printing pressure adjusting apparatus that sets a printing pressure for transfer or reprinting applied to a plate or a printing object from the blanket roll by raising and lowering the blanket roll, and A control device that synchronizes the peripheral speed of the blanket roll, to which the printing pressure for transfer or the printing pressure for retransfer is set by the printing pressure adjusting device, and the moving speed of the moving table that holds the plate or printing object is provided. Has been proposed (see, for example, Patent Document 1).

  Further, as another example of the conventional offset printing apparatus, pinions are provided at both ends of the blanket roll in the offset printing apparatus, and when the printing pressure for transfer or the printing pressure for retransfer is applied to the plate or the printing object, It has been proposed that the rack that meshes with the pinion is provided on the moving table so that the peripheral speed of the blanket roll and the moving speed of the moving table that holds the printing plate or printing object are synchronized (for example, Patent Document 2).

JP-A-5-185586 JP 2000-168031 A

  However, at the time of the transfer process or retransfer process in offset printing, in order to apply the transfer printing pressure or the retransfer printing pressure from the blanket roll to the plate or the printing object, the blanket roll is used for the plate or the printing object. The blanket roll needs to be pressed downward from the state in contact with the upper surface against the upper surface of the plate or the printing object. For this reason, a blanket is provided on the outer peripheral portion of the blanket roll, and since the blanket is an elastic body, the plate or printing object on the outer peripheral surface of the blanket is applied with the transfer printing pressure or the retransfer printing pressure. In the part which contacts an upper surface, it elastically deforms so that the said blanket may be crushed.

  Therefore, when carrying out offset printing in which the outer peripheral surface of the blanket roll is in contact with the upper surface of the plate or printing object from above, when the outer peripheral surface of the blanket roll is in contact with the upper surface of the plate or printing object from above. (The moment of contact) and the state where the printing pressure or the reprinting printing pressure is applied to the plate or the printing object from the blanket roll, the elastic deformation generated in the blanket with the application of each printing pressure. The actual condition is that the distance from the center of rotation of the blanket roll to the portion of the outer peripheral surface of the blanket roll that is in contact with the plate or the upper surface of the printing object is changed by the amount of collapse.

  Therefore, a state in which a printing pressure or a reprinting printing pressure is applied to a plate or a printing object from a blanket roll required for performing the above-described transfer processing or retransfer processing, that is, the blanket The distance from the center of rotation of the blanket roll when the crushing margin of elastic deformation accompanying the application of each printing pressure is occurring to the portion of the outer peripheral surface of the blanket roll that is in contact with the upper surface of the plate or printing object Even when the peripheral speed of the contact portion in the case of the radius of rotation is synchronized with the moving speed of the plate or the printing target, the outer peripheral surface of the blanket roll comes into contact with the upper surface of the plate or the printing target (contacts). From the moment, the blanket roll is urged downward, and the transfer printing pressure or retransfer printing pressure is applied to the plate or the printing object from the blanket roll. In the meantime, since the collapse allowance of the elastic deformation of the blanket is different from the state in which the transfer printing pressure or the retransfer printing pressure is applied, the movement speed of the plate or the printing object The actual situation is that synchronization is lost.

  Therefore, when the outer peripheral surface of the blanket roll comes into contact with the upper surface of the plate or the printing target (the moment of contact), the blanket roll is urged downward to transfer the transfer from the blanket roll to the plate or the printing target. Until the printing pressure for printing or the printing pressure for retransfer comes to be applied, the blanket brought into contact with the plate or the blanket with respect to the moving table holding the plate or the printing object due to the synchronization shift. An external force is applied from the roll, causing a problem that the trajectory reproducibility of the moving table (plate and printing target) is lowered.

  What is described in the above-mentioned Patent Document 1 is a state in which the height position of the blanket roll is preliminarily disposed at a height position for applying a printing pressure for transfer or a printing pressure for retransfer to a plate or a printing object by a printing pressure adjusting device. Then, after synchronizing the peripheral speed of the blanket roll and the moving speed of the moving table holding the printing plate or printing object, the printing pattern transfer process from the plate to the outer peripheral surface of the blanket roll, and the blanket The upper surface of the printing plate and the upper surface of the printing target, in which the reprinting process of the printing pattern from the outer peripheral surface of the roll to the printing target is performed, and the rotated blanket roll is held on the moving moving table It is not intended to contact the top from above. Therefore, the problem which arises in the offset printing apparatus of the type which contacts the outer peripheral surface of a blanket roll as mentioned above to the plate | board or the upper surface of printing object from upper direction cannot be solved, and the solution method is not suggested.

  When the height position of the blanket roll is set to a height position at which the printing pressure for transfer or the printing pressure for retransfer is applied to the plate or the printing object, both ends of the blanket roll are described in Patent Document 2. By engaging the pinion provided on the rack with the rack provided on the moving table, the peripheral speed of the blanket roll and the moving speed of the moving table holding the plate or printing object are synchronized. Therefore, from the time when the outer peripheral surface of the blanket roll comes into contact with the upper surface of the plate or the upper surface of the printing object until the printing pressure or transfer printing pressure is applied to the plate or the printing object, both end portions of the blanket roll Since the rack provided on the rack and the pinion provided on the moving table are not engaged with each other, the peripheral speed of the blanket roll is not synchronized with the moving speed of the moving table holding the plate and the printing target. Therefore, an external force is applied to the moving table from the blanket roll through the plate or the printing target, and the trajectory reproducibility of the moving table (plate and printing target) cannot be ensured.

  Therefore, the present invention relates the peripheral speed of the portion of the outer peripheral surface of the blanket roll that contacts the plate and the printing target and the moving speed of the plate and the printing target, and the outer peripheral surface of the blanket roll contacts the upper surface of the plate and the upper surface of the printing target. It is intended to provide an offset printing method and apparatus for improving printing accuracy by improving trajectory reproducibility of a plate and a printing object by synchronizing from the time of transfer to the end of transfer and retransfer. .

  In order to solve the above-mentioned problems, the present invention corresponds to claim 1, wherein the outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the plate moving in one direction from above with the transfer printing pressure. After carrying out the transfer process of the printing pattern from the plate to the blanket roll, the outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the printing object moving in one direction with the retransfer printing pressure from above, In the offset printing method for causing the printing pattern to be re-transferred from the blanket roll to the printing object, the plate has a synchronization radius between the upper surface of the plate and the rotation center of the blanket roll. The peripheral speed of the synchronization obtained from the product of the synchronous radius and the angular velocity of the blanket roll is brought into contact with the upper surface of the plate. From the first time until the end of the transfer process, the plate is synchronized with the moving speed of the plate, and the space between the upper surface of the printing target and the rotation center of the blanket roll is used as a synchronizing radius for the printing target. When the retransfer process is completed from when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the print target, the synchronous peripheral speed obtained from the product of the synchronous radius for the print target and the angular velocity of the blanket roll. Up to this point, the offset printing method is configured to be synchronized with the moving speed of the printing target.

  According to claim 2, the peripheral speed of the blanket roll is adjusted so that the outer peripheral surface of the blanket roll is subjected to a printing pattern transfer process after the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the plate. The blanket is synchronized with the moving speed of the plate until it is separated from the upper surface of the plate, and the blanket roll is contacted with the upper surface of the printing target, and then the transfer pattern is re-transferred and the blanket is transferred. The configuration is such that the outer peripheral surface of the roll is synchronized with the moving speed of the printing object until the outer surface of the roll is separated from the upper surface of the printing object.

  Furthermore, in accordance with claim 3, the outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the plate moving in one direction by the printing drive pressure from above by the lifting drive mechanism, and the blanket roll is transferred from the plate. After the printing pattern is transferred to the outer peripheral surface of the rotated blanket roll, the upper and lower drive mechanisms are brought into contact with the upper surface of the printing object moving in the one direction with the retransfer printing pressure from above. In an offset printing apparatus capable of performing a retransfer process of a printing pattern from the blanket roll to the printing object, a rotation angle detector for measuring a rotation angle of the blanket roll, the plate, and the printing object A position detector for detecting the moving position, and a synchronization half for the plate between the upper surface of the plate and the rotation center of the blanket roll. And a peripheral speed for synchronization from the product of the angular velocity of the blanket roll determined based on the rotational angle measured by the rotational angle detector, and based on the synchronous peripheral speed and the detection signal of the position detector The function of synchronizing the movement speed of the plate obtained in this manner, the radius for synchronization between the upper surface of the printing object and the rotation center of the blanket roll, and the rotation angle measured by the rotation angle detector. A function for obtaining the peripheral speed for synchronization from the product of the angular velocity of the blanket roll determined based on the synchronous peripheral speed and the moving speed of the print target determined based on the detection signal of the position detector; An offset printing apparatus provided with a controller having

  Corresponding to claim 4, in claim 3, a lift distance sensor for measuring the lift distance of the blanket roll by the lift drive mechanism is provided, and each controller radius is set in the controller, and the blanket roll retract height is provided. It is configured to have a function to be obtained based on the distance between the rotation center of the blanket roll at the position, the upper surface of the plate and the upper surface of the printing object, and the lift distance measured by the lift distance sensor.

  According to the offset printing method and apparatus of the present invention, printing from the plate to the blanket roll is performed by bringing the outer peripheral surface of the rotated blanket roll into contact with the upper surface of the plate moving in one direction from above with the printing pressure for transfer. After performing the pattern transfer process, the outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the printing object moving in the one direction from above with the printing pressure for retransfer, so that the blanket roll is transferred to the printing object. In the offset printing method in which the retransfer process of the printing pattern is performed, the synchronization radius for the plate and the blanket are set between the upper surface of the plate and the rotation center of the blanket roll. Synchronous peripheral speed determined from the product of the roll angular velocity and the above-mentioned when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the plate. Until the end of the copying process, the printing plate is synchronized with the moving speed of the plate, and a space between the upper surface of the printing object and the rotation center of the blanket roll is used as a synchronizing radius for the printing object. The synchronous peripheral speed obtained from the product of the synchronous radius and the angular velocity of the blanket roll is from the time when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the printing object to the time when the retransfer process is completed. An offset printing method having a configuration that synchronizes with a moving speed of a printing target, and an outer peripheral surface of a rotated blanket roll is brought into contact with an upper surface of a printing plate that moves in one direction from above by a printing pressure for transfer. Then, after performing the transfer process of the printing pattern from the plate to the blanket roll, the outer peripheral surface of the rotated blanket roll, A printing pattern is retransferred from the blanket roll to the printing object by contacting the upper surface of the printing object moving in the one direction with a printing pressure for retransfer from above by the lifting drive mechanism. In the offset printing apparatus, the apparatus includes a rotation angle detector that measures a rotation angle of the blanket roll, a position detector that detects a movement position of the plate and the printing object, and an upper surface of the plate and a rotation center of the blanket roll. The synchronous peripheral speed is obtained from the product of the synchronous radius for the printing plate and the angular velocity of the blanket roll determined based on the rotational angle measured by the rotational angle detector, and the synchronous peripheral speed A function of synchronizing the moving speed of the plate obtained based on the detection signal of the position detector, and the rotation of the upper surface of the printing object and the blanket roll. The peripheral speed for synchronization is obtained from the product of the radius of synchronization for printing between the center of rotation and the angular velocity of the blanket roll determined based on the rotation angle measured by the rotation angle detector, and the synchronization Since the offset printing apparatus is provided with a controller having a function of synchronizing the peripheral speed and the moving speed of the printing object obtained based on the detection signal of the position detector, the outer peripheral surface of the blanket roll is The external force is applied to the plate from the blanket roll until the plate is brought into contact with the upper surface of the plate and then the required printing pressure is applied to the plate until the transfer of the printing pattern to the blanket roll is completed. The blanket roll is brought into contact with the upper surface of the printing object from above, and then the printing object is applied to the printing object. By the action of re-transfer printing pressure needed, until retransfer printing pattern for the blanket roll is completed, to the printed from the blanket roll, it is possible to prevent the by the action of an external force. Therefore, the reproducibility of the plate and the printing target can be ensured, and the printing accuracy can be improved. Moreover, damage to the blanket roll due to friction between the blanket roll and the plate and the printing object can be reduced.

It is a schematic side view which shows one Embodiment of the offset printing method and apparatus of this invention. FIG. 2 is a partially cut side view showing an enlarged transfer mechanism portion in the offset printing apparatus of FIG. 1. It is an AA direction arrow line view of FIG. It is a BB direction arrow line view of FIG. It is a schematic diagram which shows the control structure of the controller with which the offset printing apparatus of FIG. 1 is equipped. FIG. 1 shows a time chart when offset printing is performed by the offset printing apparatus of FIG. 1, (A) is a diagram showing a change in the synchronization radius of the blanket roll, (B) is a diagram showing a change in the angular velocity of the blanket roll, (C) is a diagram showing the movement speed (table movement speed) of the plate table and the printing target table. FIG. 6 shows the state of the blanket roll and the plate table at each time of FIG. 6, (A) is a schematic diagram showing the state at time T0, and (B) is a schematic showing the state between time T1 and time T2. (C) is a schematic diagram showing a state at time T2, and (d) is a schematic diagram showing a state between time T2 and time T3. FIG. 6 shows the state of the blanket roll and the plate table at each time after T4 in FIG. 6, (A) is a schematic diagram showing the state at time T4, (B) is a schematic diagram showing the state at time T5, (C) is a schematic diagram showing a state at time T6.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIGS. 1 to 8 (A), (B), and (C) show an embodiment of an offset printing method and apparatus according to the present invention.

  1 to 5 show an offset printing apparatus according to the present invention used in the offset printing method according to the present invention. A guide rail 2 extending in one direction, for example, two by one, is provided above a horizontal base 1. A set of guide rails 2 is provided, and a plate table 4 on which a plate 3 such as an intaglio is attached and held on the guide rail 2, and a printing target table 6 on which a printing target 5 such as a substrate is attached and held on the upper surface. Are arranged in order from one end side (left side in FIG. 1) in the longitudinal direction (X-axis direction) of the guide rail 2 so as to be slidable through the respective guide blocks 7. The plate table 4 and the printing target table 6 are each provided with a table driving device 8 such as a linear motor. The table driving device 8 allows the plate table 4 and the printing target table 6 to be connected. In addition, it is possible to travel (move) individually along the guide rail 2.

  Further, a linear scale 9 as a position detector is provided on the gantry 1 in parallel with the guide rail 2, and the linear scale 9 allows the length of the guide rail 2 of the plate table 4 and the printing target table 6 to be long. A position along the direction, that is, an absolute position in the X-axis direction based on a required point in the X-axis direction can be detected together.

  Further, at a position corresponding to the longitudinal intermediate portion of the guide rail 2 on the gantry 1, it extends in the horizontal direction (Y-axis direction) perpendicular to the longitudinal direction of the guide rail 2 above the guide rail 2. A roll support frame 12 that holds the blanket roll 10 rotatably via rotation shafts 11a and 11b provided at both ends in the left-right direction (a direction perpendicular to the longitudinal direction of the guide rail 2), In order to rotationally drive the blanket roll 10, a rotational drive motor 13 as a rotational drive connected to one rotational shaft 11 a of the blanket roll 10, and the blanket roll 10 rotationally driven by the rotational drive motor 13. Encoder 14 as a rotation angle detector for measuring the rotation angle of the roll, and the roll support frame 12, the elevation drive mechanism 15 for raising and lowering the blanket roll 10 and the blanket roll 10 raised and lowered by the elevation drive mechanism 15 from a certain reference height position, for example, the blanket roll retracting height position A transfer mechanism unit 17 including a lift distance sensor 16 for measuring the lift distance is provided.

  Furthermore, the vertical distance between the height position Za of the rotation center O of the blanket roll 10 and the upper surface height position Zb of the plate 3 or the printing object 5 is set as a virtual synchronization radius ( (Hereinafter simply referred to as a synchronization radius) R, and when performing transfer processing or retransfer processing in offset printing, the blanket roll 10 of the blanket roll 10 that is obtained based on the synchronization radius R and the measured value of the encoder 14 is used. The value calculated as the product of the angular velocity ω, that is, the circumferential moving speed ((R · ω) of the virtual circumferential surface of the synchronizing radius R around the rotation center O of the blanket (hereinafter referred to as synchronization) Peripheral speed) and the moving speed of the plate table 4 holding the plate 3 obtained based on the detection signal of the linear scale 9 and the printing object table 6 holding the printing object 5 In a state where v is always synchronized (matched) (v = R · ω), the blanket roll 10 is placed above the upper surface of the plate 3 on the plate table 4 and the printing target 5 on the printing target table 6. The blanket roll 10 in contact with the upper surface of the plate 3 on the plate table 4 or the printing target 5 on the printing target table 6, and the plate 3 or the plate 3 from the blanket roll 10. The offset printing apparatus of the present invention is configured by including a controller 18 having a function of performing a process of applying a certain transfer printing pressure or retransfer printing pressure to the printing object 5.

  More specifically, as shown in FIGS. 1 to 4, the transfer mechanism section 17 includes two guide mechanisms 2 on the left and right outer sides of the intermediate portion in the longitudinal direction of the guide rail 2 with a predetermined interval in the longitudinal direction of the guide rail 2. Columns 19 each having a required height dimension, and beam members 20 that are arranged so as to cross over the required dimension of the intermediate portion in the longitudinal direction of the guide rail 2 and integrally connect the tops of the columns 19 together. A portal-type frame 21 provided is provided.

  The roll support frame 12 has a structure in which a pair of bearing housings 22a and 22b are integrally connected to both left and right ends of a mounting member 23 extending in the left and right direction, and each bearing housing of the roll support frame 12 is provided. The rotating shafts 11a and 11b provided at both ends of the blanket roll 10 are rotatably supported by 22a and 22b through bearings 24, and the bearing housings at both the left and right ends of the roll support frame 12 are supported. 22a and 22b are disposed between the two columns 19, and are attached to the columns 19 so as to be movable in the vertical direction via linear guides 25 provided in the columns 19 respectively. It is.

  Further, the roll support is provided on the beam member 20 of the portal frame 21 at a position above the bearing housings 22 a and 22 b of the roll support frame 12 via the bearing housings 22 a and 22 b and the mounting member 23. As an elevating drive mechanism 15 for elevating the blanket roll 10 integrally with the frame 12, for example, a ball screw mechanism 15 having the following configuration (for the sake of convenience, the same reference numerals as those of the elevating drive mechanism 15 are provided). Each is provided.

  Each ball screw mechanism 15 has a bearing 27 at a position near the upper end portion of the screw shaft 26 extending in the vertical direction at a position above the bearing housings 22a and 22b of the roll support frame 12 in the beam member 20. And a gear box 29 in which a lift drive motor 28 such as a servo motor as a lift drive device is connected to a position above the bearings 27 on the beam member 20 is supported. A projecting end portion of each screw shaft 26 that protrudes upward from each bearing 27 is connected to the output side of each gear box 29, and is further connected to a lower portion of each screw shaft 26. Each of the nut members 31 to be screwed is installed on the mounting member 23 of the roll support frame 12.

  As a result, each screw shaft 26 is driven to rotate via each gear box 29 by the operation of each lifting drive motor 28 in each ball screw mechanism 15, so that each screw member 26 is rotated via each nut member 31. The blanket roll 10 can be moved up and down integrally with the roll support frame 12.

  The blanket roll 10 is moved up and down by the ball screw mechanisms 15 at the upper end of the stroke end by pulling the blanket roll 10 up to the blanket roll retracting height position. The height position of the lower end portion of the outer peripheral surface 10 is a certain dimension above the upper surface height position Zb of the plate 3 held on the plate table 4 and the printing target 5 held on the printing target table 6. It can be separated. Thereby, in the state where the blanket roll 10 is raised to the blanket roll retracted height position, the plate table 4 holding the plate 3 and the printing target table 6 holding the printing target 5 are transferred to the blanket roll. 10 can be passed therethrough without interfering with 10.

  On the other hand, at the stroke end on the lower end side of the raising / lowering range of the blanket roll 10 by the ball screw mechanisms 15, the plate 3 or the printing target table in which the lower end portion of the outer peripheral surface of the blanket roll 10 is held on the plate table 4. 6 is set so that the blanket roll 10 can be lowered until it is arranged slightly below the upper surface height position Zb of the printing object 5 held on the upper surface 6. As a result, in each of the ball screw mechanisms 15, the lower end portion of the outer peripheral surface of the blanket roll 10 is the plate 3 held on the plate table 4 disposed immediately below it, or the printing target 5 held on the printing target table 6. The blanket roll 10 can be urged downward from the state in contact with the plate 3. By this urging, the blanket roll 10 is held on the plate table 4 or the printing target table. 6 is pressed against the upper surface of the printing object 5 held on the plate 6 so that a transfer printing pressure or a re-transfer printing pressure can be applied to the plate 3 or the printing object 5.

  Further, each of the ball screw mechanisms 15 is individually provided with a load cell 33 as a printing pressure measuring sensor at a joint portion between the nut member 31 and the mounting member 23. As a result, when the transfer pressure or retransfer pressure is applied to the plate 3 or the printing object 5 from the blanket roll 10, the reaction force of each printing pressure is applied from the blanket roll 10 to the roll support frame 12 and Each of the load cells 33 is transmitted to the ball screw mechanism 15 via the mounting member 23 and each load cell 33. At this time, the magnitude of the reaction force corresponding to each printing pressure is measured by each load cell 33. By doing so, the printing pressure applied to the plate 3 and the printing object 5 from the blanket roll 10 can be measured.

  Furthermore, for example, an encoder 16 (for the sake of convenience, the same reference numeral as that of the lift distance sensor 16 is attached) is provided for each of the lift drive motors 28 for measuring the lift distance of the blanket roll 10. And so on). Accordingly, the rotation amount of each screw shaft 26 via each gear box 29 can be calculated based on the rotation amount signal of each lifting drive motor 28 detected by each encoder 16. Movement along the longitudinal direction (vertical direction) of the screw shaft 26 of the blanket roll 10 that moves up and down integrally with the nut members 31 screwed into the screw shafts 26 according to the rotation amount of the screw shafts 26. The distance, that is, the elevation distance of the blanket roll 10 can be measured.

  A reduction gear 32 connected to the rotation drive motor 13 is attached to the outer surface of one bearing housing 22a of the roll support frame 12, and the one bearing housing 22a is connected to an output shaft (not shown) of the reduction gear 32. One rotation shaft 11a of the blanket roll 10 supported on the rotating shaft 11a is coupled, and thereby the blanket roll 10 is driven to rotate via the speed reducer 32 by the operation of the rotation driving motor 13. I can do it. Further, the rotation drive motor 13 is provided with an encoder 14 as a rotation angle detector, so that the rotation amount signal of the rotation drive motor 13 detected by the encoder 14 can be used as a basis. In addition, the rotation angle of the blanket roll 10 (rotation angle with respect to a certain position in the circumferential direction) can be measured.

  As shown in FIG. 5, the controller 18 is based on the table position detection signals of the plate table 4 and the printing target table 6 input from the linear scale 9 provided on the gantry 1. A command is given to the table driving device 8 for the plate table 4 and the printing target table 6 so that the position, moving direction (traveling direction) and moving speed (traveling speed) v of the tables 4 and 6 can be controlled. A table traveling control unit 18a is provided.

  Further, the controller 18 includes a roll rotation control unit 18 b and a roll lifting control unit 18 c for controlling the transfer mechanism unit 17.

  The roll rotor control unit 18b is configured to detect an angular velocity (rotation) of the blanket roll 10 based on a measurement signal of the rotation angle of the blanket roll 10 input from an encoder 14 attached to the rotation drive motor 13 of the blanket roll 10. (Speed) ω and an angular posture are obtained and detected, and a command is given to the rotation drive motor 13 to control the angular velocity ω and the angular posture of the blanket roll 10.

  The roll raising / lowering control unit 18c uses the blanket roll retracted height position as a reference height position as a reference on the basis of a signal input from the encoder 16 attached to each raising / lowering drive motor 28. A function of calculating and calculating a lifting distance of 10, a function of detecting the height position Za of the rotation center O of the blanket roll 10 based on the determined lifting distance of the blanket roll 10, and the detected blanket Based on information on the height position Za of the rotation center O of the roll 10, a function is provided for controlling the elevation of the blanket roll 10 by giving a command to the elevation drive motor 28 of each ball screw mechanism 15. . Further, a signal inputted from the load cell 33 serving as a printing pressure measuring sensor, that is, the blanket roll 10 is brought into contact with the plate 3 or the printing object 5 to the roll raising / lowering control unit 18c. Based on the measurement signals of the respective printing pressures at the time of application, a function is also provided for controlling the elevation of the blanket roll 10 by giving a command to the elevation drive motor 28 of each ball screw mechanism 15 as will be described later. It is like that.

  In the controller 18, the table travel control unit 18a, the roll rotation control unit 18b, and the roll lifting control unit 18c can be controlled synchronously with each other.

  In the offset printing apparatus of the present invention, because of the necessity of performing offset printing, as shown in FIG. 1, the longitudinal direction of the guide rail 2 is set at a position corresponding to one end portion of the guide rail 2 in the longitudinal direction on the gantry 1. A plate table standby area 34 is provided so that the plate table 4 can be moved to the one end in the direction and can be made to stand by, and the plate 3 held on the plate table 4 can be exchanged. . Further, the printing object table 6 is moved to the other end in the longitudinal direction of the guide rail 2 at a position corresponding to the other end in the longitudinal direction of the guide rail 2 on the gantry 1 and the printing is performed in a state where the printing target table 6 is in a standby state. A print target installation area 35 is provided for attaching a new print target 5 to the target table 6 and removing the print target 5 after retransfer (printing) processing. Further, a portion that does not interfere with any of the transfer mechanism 17, the plate table standby area 34, and the print target installation area 35 on the gantry 1, for example, the plate table standby area 34 and the transfer mechanism on the gantry 1. Between the unit 17, an inking device 36 for inking the plate 3 held on the plate table 4 is provided.

  Next, the offset printing method of the present invention will be described in detail according to the specific control contents by the controller 18.

  That is, when performing offset printing using the offset printing apparatus of the present invention having the above-described configuration, the blanket roll in a state where the ball screw mechanism 15 in the transfer mechanism unit 17 is arranged in the blanket roll retracted height position in advance. 10, the size of the gap formed between the lower end of the outer peripheral surface of the blanket roll 10 and the upper surface of the plate 3 on the plate table 4 and the printing target 5 on the printing target table 6 disposed below the blanket roll 10. For example, it is measured accurately using a block gauge, and as shown in FIG. 7 (a), the measured value Zc is based on the design data of the blanket roll 10 or after the blanket roll 10 is manufactured. By adding the roll radius dimension r, which is known by actual measurement, the plate 3 and the mark held on the plate table 4 are added. Vertical direction from the top surface height position Zb of the printing object 5 held on the object table 6 to the rotation center O of the blanket roll 10 in the state where the blanket roll is retracted at the reference height position Zo. The distance H is obtained and stored in the controller 18. At this time, if the upper surface height position Zb of the plate 3 held on the plate table 4 and the upper surface height position Zb of the printing object 5 held on the printing object table 6 are different from each other, If the vertical distance H from the upper surface height position Zb to the rotation center O of the blanket roll 10 in the state where the blanket roll is retracted at the reference height position Zo is determined individually. Good.

  Further, the plate 3 held on the plate table 4 in the plate table standby area 34 is sent to the inking device 36 by running of the plate table 4 to ink the plate 3, and then the inking is performed. The plate table 4 holding the plate 3 passes through the lower part of the blanket roll 10 in the state where the transfer mechanism unit 17 is disposed at the blanket roll retracted height position, and the plate 3 is more offset than the transfer mechanism unit 17 during offset printing. Upstream of the direction in which the plate table 4 holding the printing object 6 and the printing object table 6 holding the printing object 5 run below the blanket roll 10 in the transfer mechanism 17 (the direction of arrow a, hereinafter referred to as the table running direction during printing). It is moved to the travel start position at the time of printing preset on the side. On the other hand, in the print target table 6, a print target 5 to be newly printed in the print target installation area 35 is placed and held.

  Further, the controller 18 includes a transfer printing pressure to be applied from the blanket roll 10 to the plate 3 on the plate table 4 during the transfer process in offset printing, and a printing target table from the blanket roll 10 during the retransfer process. The setting value related to the printing pressure for retransfer to be applied to the print object 5 on 6 is input and stored.

  In this state, first, as shown in FIG. 6 (c) and FIG. 7 (a), at time T0, a command is given to the table driving device 8 by the function of the table traveling control unit 18a of the controller 18, and the above-mentioned The plate table 4 holding the inked plate 3 disposed at the printing start position is started to run at a constant moving speed v in the printing table running direction a, and the controller By the function of the 18 roll rotation control unit 18b, a command is given to the rotation drive motor 13 of the transfer mechanism unit 17 to start the rotation of the blanket roll 10. At this time, the controller 18 is obtained on the basis of a signal input from the encoder 16 attached to each of the lift drive motors 28 by synchronous control of the table running control unit 18a and the roll rotation control unit 18b. FIG. 6B is obtained based on a synchronization radius R in the blanket roll 10 as shown in FIG. 6A and a signal input from an encoder 14 attached to the rotation drive motor 13 of the blanket roll 10. The synchronous peripheral speed (R · ω) calculated by the product of the blanket roll 10 and the angular speed ω is made to coincide with the moving speed v of the plate table 4 which is constant as shown in FIG. In order to achieve this, the control for always matching the angular velocity ω of the blanket roll 10 with the value obtained by ω = v / R is started.

  At time T0, as shown in FIGS. 6 (a) and 7 (a), the blanket roll 10 is placed at the blanket roll retracted height position, and therefore the height of the rotation center O of the blanket roll 10 is high. The height position Za coincides with the reference height position Zo of the blanket roll 10 set as described above. Therefore, the synchronization radius R of the blanket roll 10 at time T0 is from the upper surface height position Zb of the plate 3 on the plate table 4 stored in the controller 18 in advance to the reference height position Zo. It coincides with the vertical distance H. Therefore, at the time T0, the controller 18 controls the angular velocity ω of the blanket roll 10 to a value obtained by ω = v / R = v / H.

  Next, as shown in FIG. 6 (a), the controller 18 starts from the reference height position Zo of the blanket roll 10 by the lift drive motors 28 by the function of the roll lift control unit 18c at time T1. Starts to descend.

  As a result, as shown in FIG. 7B, the height position Za of the rotation center O of the blanket roll 10 is lowered from the reference height position Zo. Assuming that the amount of movement of the height position Za from the reference height position Zo is the up-and-down movement amount z, the synchronizing radius R of the blanket roll 10 is from the upper surface height position Zb of the plate 3 on the plate table 4. It can be obtained by subtracting the up-and-down movement amount z from the vertical distance H to the reference height position Zo (R = H−z). Therefore, the value of the synchronization radius R of the blanket roll 10 gradually decreases.

  Even in this state, the controller 18 uses the synchronous peripheral speed (R · ω) calculated by the product of the synchronous radius R and the angular speed ω of the blanket roll 10 as the moving speed of the plate table 4. Since the control to match v is continued, the controller 18 controls the angular velocity ω of the blanket roll 10 to match the value obtained by ω = v / R = v / (H−z). Is done.

  Therefore, as shown in FIG. 6 (a), after the time T1, when the synchronization radius R decreases as the blanket roll 10 descends, the blanket roll 10 The angular velocity ω is gradually increased so as to satisfy the condition of ω = v / R. Note that, when the lowering speed of the blanket roll 10 is constant and the synchronizing radius R of the blanket roll 10 changes linearly, the change of the angular velocity ω of the blanket roll 10 that is inversely proportional to the synchronizing radius R is not linear. In FIG. 6B, the change in the angular velocity ω of the blanket roll 10 is also shown linearly for convenience of illustration.

  Thereafter, the blanket roll 10 is continuously lowered so that the center of rotation of the blanket roll 10 is obtained at time T2 shown in FIGS. 6 (a), 6 (b), and 6 (c), as shown in FIG. When the vertical movement amount z of the height position Za of O from the reference height position Zo is in the state where the blanket roll 10 is placed at the blanket roll retracting height position, the lower end of the outer peripheral surface and the plate table 4 When the measured value Zc of the gap formed between the upper plate 3 and the upper surface of the upper plate 3 coincides with the measured radius Zc of the blanket roll 10, the synchronizing radius R of the blanket roll 10 coincides with the radius r of the blanket roll ( R = H−z = (r + Zc) −Zc = r). Therefore, the lower end portion of the outer peripheral surface of the blanket roll 10 comes into contact with the edge portion on the front end side in the table running direction a during printing of the plate 3 held on the plate table 4 from above.

  In addition, as described above, the blanket roll 10 is lowered by the control. Therefore, the time T2 when the up-and-down movement amount z of the lowered blanket roll 10 coincides with the measured value Zc from the time T0. The elapsed time until is known in advance. Therefore, the movement distance from time T0 to time T2 of the plate table 4 moving at the constant movement speed v is obtained in advance, and printing of the plate 3 held on the plate table 4 by the movement distance is obtained. The printing table running start position of the plate table 4 is set at a position where the edge of the leading edge of the hour table running direction a is separated from the position immediately below the blanket roll 10 to the upstream side of the printing table running direction a. Then, the controller controls the lower end portion of the outer peripheral surface of the blanket roll 10 to come into contact with the edge portion on the front end side in the table running direction a during printing of the plate 3 held on the plate table 4 from above. 18 is performed.

  Even at the time T2, the controller 18 moves the plate table 4 using the synchronous peripheral speed (R · ω) calculated by the product of the synchronous radius R of the blanket roll 10 and the angular velocity ω. Control to match the speed v is continued. Therefore, at the time T2, the angular velocity ω of the blanket roll 10 is controlled by the controller 18 so as to coincide with the value obtained by ω = v / R = v / r. Therefore, at time T2, the synchronous peripheral speed (R · ω) of the blanket roll 10 controlled by the angular velocity ω as described above coincides with the peripheral speed (r · ω) of the outer peripheral surface of the blanket roll 10. Therefore, when the lower end of the outer peripheral surface of the blanket roll 10 contacts the upper surface of the plate 3 on the plate table 4 from above (at the moment of contact) at the time T2, the periphery of the outer peripheral surface of the blanket roll 10 is The speed and the moving speed of the plate 3 corresponding to the moving speed v of the plate table 4 are reliably synchronized.

  Thereafter, the controller 18 applies the printing pressure for transfer from the blanket roll 10 to the plate 3 on the plate table 4 by the function of the roll raising / lowering control unit 18c by the raising / lowering drive motors 28. The roll 10 is urged downward from the state in contact with the upper surface of the plate 3 on the plate table 4. Due to this downward urging, the lower end in the circumferential direction of a blanket (not shown) provided on the outer peripheral portion of the blanket roll 10 is pressed and crushed against the upper surface of the plate 3 on the plate table 4 from above. As shown in FIGS. 6 (a) and 7 (d), the position of the rotation center O of the blanket roll 10 is further lowered.

  For this reason, as shown in FIG. 7 (d), the blanket roll 10 is elastically deformed so that the blanket pressed against the upper surface of the plate 3 on the plate table 4 from above is crushed with a crushing margin Δz. In this state, the vertical movement amount z of the blanket roll 10 is such that the lower end of the outer peripheral surface of the blanket roll 10 and the upper surface height position Zb of the plate 3 on the plate table 4 are arranged at the blanket roll retracted height position. Between the measured value Zc of the gap formed between the blanket and the blanket roll 10 in the blanket roll 10. Therefore, the synchronization radius R of the blanket roll 10 at this time is calculated as R = H−z = (r + Zc) − (Zc + Δz) = r−Δz based on the relationship of H = r + Zc described above. Therefore, the synchronization radius R of the blanket roll 10 is a value obtained by subtracting the blanket collapse allowance Δz from the radius r of the blanket roll 10, that is, from the rotation center O of the blanket roll 10. At the lower end of the surface, the dimension (r−Δz) is the distance up to the portion in contact with the plate 3 on the plate table 4 in a state where the blanket is elastically deformed at the crushing allowance Δz.

  Even in this state, the controller 18 uses the synchronous peripheral speed (R · ω) calculated by the product of the synchronous radius R and the angular speed ω of the blanket roll 10 as the moving speed of the plate table 4. Since the control to match v is continued, the controller 18 controls the angular velocity ω of the blanket roll 10 to match the value obtained by ω = v / R = v / (r−Δz). Is done.

  Therefore, in the state where the blanket roll 10 is urged downward and pressed against the upper surface of the plate 3 on the plate table 4 as described above, the blanket roll 10 is not affected by the change in the blanket allowance Δz. The peripheral speed (synchronous peripheral speed) of the part in contact with the plate 3 on the plate table 4 on the outer peripheral surface is always synchronized with the moving speed of the plate 3 that matches the moving speed v of the plate table 4. It becomes a state.

  When the blanket roll 10 is pressed downward against the plate 3 on the plate table 4 as described above, the signal input from the load cell 33 is increased as the blanket collapse allowance Δz increases. Further, the contact pressure P of the blanket roll 10 to the plate 3 detected by the controller 18 gradually increases.

  Therefore, the controller 18 determines that the contact pressure P of the blanket roll 10 with respect to the plate 3 detected based on the signal input from the load cell 33 at time T3 shown in FIG. When the set value of the transfer printing pressure stored in the container 18 coincides, the lifting drive motor 28 is stopped by the function of the roll lifting control unit 18c, and the lowering of the blanket roll 10 is stopped.

  Thereby, the blanket roll 10 applies a predetermined transfer printing pressure from the blanket roll 10 to the plate 3, and comes into contact with the plate 3 on the plate table 4 on the outer peripheral surface of the blanket roll 10. The peripheral speed (synchronous peripheral speed) of the portion is synchronized with the movement speed v of the plate table 4 which is the movement speed of the plate 3.

  Therefore, as shown in FIG. 6 (a), the controller 18 makes the transfer printing pressure constant from the time T3 to the time T4 when the printing pattern transfer process to the blanket roll 10 ends. While keeping the synchronizing radius R of the blanket roll 10 constant and maintaining the angular velocity ω of the blanket roll 10 constant as shown in FIG. The printing pattern transfer process from the plate 3 to the blanket roll 10 is performed so as to maintain the synchronized state of the peripheral speed (synchronous peripheral speed) and the moving speed of the plate 3.

  Thereafter, when the transfer process is completed at the time T4, the controller 18 drives the lifting drive motors 28 in the direction opposite to that when the blanket roll 10 is lowered by the roll lifting control unit 18c. Then, as shown in FIGS. 6A and 8A, the blanket roll 10 starts to rise.

  When the rising of the blanket roll 10 is started at time T4 as described above, the position of the rotational center O of the blanket roll 10 relative to the rotational center O of the blanket roll 10 gradually rises. As shown, the synchronization radius R of the blanket roll 10 gradually increases.

  At this time, while the blanket is pressed against the plate 3 on the plate table 4 at the lower end portion of the outer peripheral surface of the blanket roll 10 and there is a crushing margin Δz in the blanket, as shown in FIG. Similarly, the vertical movement amount z of the blanket roll 10 with respect to the reference height position Zo is set on the plate table 4 and the lower end of the outer peripheral surface of the blanket roll 10 placed at the blanket roll retracted height position. This is equal to the sum of the measured value Zc of the gap between the upper surface height position Zb of the plate 3 and the blanket collapse allowance Δz. Therefore, the synchronization radius R of the blanket roll 10 at this time is R = H−z = (r + Zc) − (Zc + Δz) = r−Δz, as in the case of FIG. Therefore, also in this case, the synchronization radius R of the blanket roll 10 is r−Δz, that is, the crushing margin Δz from the rotation center O of the blanket roll 10 to the lower end portion of the outer peripheral surface of the blanket roll 10. In the state where the blanket is elastically deformed, the dimension is equal to the dimension up to the portion in contact with the plate 3 on the plate table 4.

  Even in this state, the controller 18 uses the synchronous peripheral speed (R · ω) calculated by the product of the synchronous radius R and the angular speed ω of the blanket roll 10 as the moving speed of the plate table 4. Since the control to match v is continued, the controller 18 causes the angular velocity ω of the blanket roll 10 to match the value obtained by ω = v / R = v / (r−Δz). Be controlled. Accordingly, the peripheral speed (synchronous peripheral speed) of the portion of the outer peripheral surface of the blanket roll 10 that is in contact with the plate 3 on the plate table 4 regardless of the change in the blanket allowance Δz of the blanket is the plate. The state is always synchronized with the moving speed of the plate 3 that matches the moving speed v of the table 4.

  Thereafter, as shown in FIG. 8 (b) at time T5 in FIG. 6 (a), the outer peripheral surface of the blanket roll 10 immediately before the blanket roll 10 is separated from the upper surface of the plate 3 on the plate table 4. When the lower end of the blanket is simply in contact with the upper surface of the plate 3 on the plate table 4 in a state in which the elastic deformation of the blanket has been eliminated, the synchronizing radius R of the blanket roll 10 is equal to that of the blanket roll 10. Matches the radius r.

  Even at the time T5, the controller 18 moves the plate table 4 using the synchronizing peripheral speed (R · ω) calculated by the product of the synchronizing radius R of the blanket roll 10 and the angular velocity ω. Since the control to match the speed v is continued, at the time T5, the angular speed ω of the blanket roll 10 matches the value obtained by the controller 18 as ω = v / R = v / r. Be controlled.

  Therefore, at the time T5, the synchronous peripheral speed (R · ω) determined based on the angular velocity ω of the blanket roll 10 controlled as described above becomes the peripheral speed (r · ω) of the outer peripheral surface of the blanket roll 10. Therefore, when the lower end of the outer peripheral surface of the blanket roll 10 separates upward from the upper surface of the plate 3 on the plate table 4 (at the moment of separation) at the time T5, the outer peripheral surface of the blanket roll 10 is also obtained. And the movement speed of the plate 3 that coincides with the movement speed v of the plate table 4 are reliably synchronized.

  After the blanket roll 10 is separated from the plate 3 on the plate table 4 at the time T5, the controller 18 raises the blanket roll 10 by the function of the roll lifting / lowering control unit 18c, and FIG. At time T6, as shown in FIG. 8C, the blanket roll 10 is returned to the blanket roll retracted height position which is the initial state position.

  At this time, the controller 18 uses the function of the roll rotation control unit 18b to change the angular velocity ω of the blanket roll 10 to the blanket accompanying the rise of the blanket roll 10, as shown in FIGS. According to the change of the synchronization radius R of the roll 10, it may be changed so that ω = v / R as in the period from the time T1 to the time T2, but at the time T5, the blanket roll 10 At any time after the plate is separated from the plate 3 on the plate table 4, the rotational drive of the blanket roll 10 is stopped, and the blanket roll 10 in the rotation stopped state is returned to the blanket roll standby height position. May be.

  Thereafter, when the process accompanying the transfer process of the printing pattern from the plate 3 on the plate table 4 to the blanket roll 10 is completed as described above, the controller 18 performs the printing held on the printing target table 6. Steps performed on the plate 3 held on the plate table 4 as shown in FIGS. 6 (a), (b) and (c) to FIGS. The transfer process is replaced with the retransfer process, the plate 3 is replaced with the print target 5, the plate table 4 is replaced with the print target table 6, and the transfer printing pressure is replaced with the retransfer printing pressure. A retransfer (printing) process of the print pattern for the print target 5 on the print target table 6 is performed from the blanket roll 10.

  As described above, according to the offset printing method and apparatus of the present invention, when performing the transfer process in the offset printing, the height position Za of the rotation center O of the blanket roll 10 and the plate held on the plate table 4 are used. 3 for synchronizing the blanket roll 10 obtained from the product of the radius R for synchronization of the plate 3 of the blanket roll 10 and the angular velocity ω of the blanket roll 10, which is the vertical distance from the upper surface height position Zb of 3. With the peripheral speed synchronized with the movement speed of the plate 3 that matches the movement speed v of the plate table 4, the outer peripheral surface of the blanket roll 10 is held on the upper surface of the plate 3 held on the plate table 4. The blanket roll 10 in contact with the upper surface of the plate 3 is urged downward to crush the blanket of the blanket roll 10. And the step of increasing the contact pressure with respect to the plate 3 to a predetermined transfer printing pressure is performed, so that the outer peripheral surface of the blanket roll 10 is held on the plate table 4. When contacting the upper surface from above (the moment of contact), and when applying a predetermined transfer printing pressure to the plate 3 by urging the blanket roll 10 in contact with the upper surface of the plate 3 downward The peripheral speed of the portion in contact with the plate 3 in the outer peripheral portion of the blanket roll 10 can be always synchronized (coincided) with the moving speed of the plate 3 moving together with the plate table 4.

  Further, the predetermined transfer printing pressure is applied to the plate 3 from the blanket roll 10 in a state where the synchronizing peripheral speed of the blanket roll 10 is synchronized with the moving speed of the plate 3 that matches the moving speed v of the plate table 4. A step of transferring a printing pattern from the plate 3 to the blanket roll 10 in the applied state, a step of lifting the blanket roll 10 after the transfer is completed, and eliminating elastic deformation of the blanket, and the blanket And the step of separating the outer peripheral surface of the roll 10 from the upper surface of the plate 3 on the plate table 4, so that the plate 3 is in contact with the plate 3 at the outer peripheral portion of the blanket roll 10 during each step. The peripheral speed of the existing portion can be always synchronized (matched) with the moving speed of the plate 3 moving together with the plate table 4.

  Therefore, when the blanket roll 10 synchronization radius R changes with the increase / decrease of the blanket collapse allowance Δz between the time when the blanket roll 10 is brought into contact with the plate 3 from above and the time when the blanket roll 10 is separated. However, it is possible to prevent an external force from acting on the plate table 4 from the blanket roll 10 through the plate 3.

  Further, when performing the retransfer process in the offset printing, it is between the height position Za of the rotation center O of the blanket roll 10 and the upper surface height position Zb of the printing target 5 held on the printing target table 6. The synchronous peripheral speed of the blanket roll 10 obtained from the product of the synchronizing radius R for the printing object 5 of the blanket roll 10 and the angular velocity ω of the blanket roll 10, which is the vertical distance, is the The step of bringing the outer peripheral surface of the blanket roll 10 into contact with the upper surface of the printing object 5 held on the printing object table 6 from above while being synchronized with the movement speed of the printing object 5 that matches the movement speed v. Then, the blanket roll 10 in contact with the upper surface of the printing object 5 is urged downward, and the blanket of the blanket roll 10 is crushed. Since the step of deforming and increasing the contact pressure with respect to the print object 5 to a predetermined retransfer printing pressure is performed, the print object 5 in which the outer peripheral surface of the blanket roll 10 is held on the print object table 4. When the upper surface of the printing object 5 is contacted from above (the moment of contact), and the blanket roll 10 that is in contact with the upper surface of the printing object 5 is urged downward to press the printing object 5 with a predetermined retransfer printing pressure. , The peripheral speed of the portion of the outer periphery of the blanket roll 10 that is in contact with the printing object 5 is always synchronized (matched) with the moving speed of the printing object 5 that moves together with the printing object table 6. be able to.

  Further, the blanket roll 10 synchronizes with the moving speed of the printing object 5 that matches the moving speed v of the printing object table 6, and the blanket roll 10 applies the predetermined re-transfer to the printing object 5. A step of re-transferring the print pattern from the blanket roll 10 to the printing object 5 with the transfer printing pressure applied, and a step of lifting the blanket roll 10 after the re-transfer is completed to cancel the elastic deformation of the blanket. And the step of separating the outer peripheral surface of the blanket roll 10 from the upper surface of the print target 5 on the print target table 6. The peripheral speed of the portion in contact with the printing object 5 is the moving speed of the printing object 5 that moves together with the printing object table 6. It can be synchronized (matched) to.

  Accordingly, when the blanket roll 10 is brought into contact with the printing object 5 from above and separated, the synchronization radius R of the blanket roll 10 changes as the blanket collapse allowance Δz increases or decreases. In addition, it is possible to prevent an external force from acting on the printing target table 6 from the blanket roll 10 through the printing target 5.

  Therefore, the trajectory reproducibility of the plate table 4 and the printing target table 6 can be ensured, and the printing accuracy can be improved.

  Further, when the blanket roll 10 is brought into contact with the plate 3 and the printing object 5, the blanket roll 10 is displaced in the direction along the traveling direction of the corresponding tables 4 and 6 between the plate 3 and the printing object 5. As the external force that causes the loss of action no longer acts, the wear of the blanket roll 10 can be reduced.

  Further, the controller 18 measures the contact pressure applied from the blanket roll 10 to the plate 3 on the plate table 4 and the printing target on the printing target table 6 from the signal input from the load cell 33. When the blanket roll 10 is brought into contact with the plate 3 or the printing object 5 and is lowered downward, the contact pressure is required for the transfer process or the retransfer process. Since the process is performed until the pressure is reached, it is possible to easily cope with the change in the printing pressure for transfer and the printing pressure for retransfer. Moreover, even if the transfer printing pressure and the retransfer printing pressure are changed in this way, the peripheral speeds of the portions of the outer peripheral portion of the blanket roll 10 that are in contact with the plate 3 and the printing object 5 are changed to the corresponding tables 4, 4. There is no problem in synchronizing (matching) with the moving speed of the plate 3 and the printing object 5 moving together with the printing object 6.

  In addition, this invention is not limited only to the said embodiment, For example, as the raising / lowering drive mechanism 15 of the blanket roll 10, the blanket roll retraction height position which sets the blanket roll 10 to a certain height position Then, the blanket roll 10 is brought into contact with the upper surface of the plate 3 held on the plate table 4 and the printing target 5 held on the printing target table 6 from above, and the blanket roll 10 is urged downward. If the blanket roll 10 can be moved up and down to a height position where the printing pressure or transfer pressure is applied to the plate 3 or the printing object 5, any type of lifting drive mechanism other than the ball screw mechanism is adopted. Also good.

  The lift distance sensor 16 is not limited to the encoder 16 attached to the lift drive motor 28 as long as the lift distance of the blanket roll 10 can be detected. For example, the lift distance sensor 16 is not limited to the portal frame 21 of the transfer mechanism section 17. A linear scale may be provided in the vertical direction between the column 19 and the bearing housings 11a and 11b of the roll support frame 12, and the linear scale may be used as a lift distance sensor.

  In the above embodiment, the printing pressure measuring sensor for measuring the printing pressure for transfer and the printing pressure for retransfer is interposed between the nut member 31 of the ball screw mechanism 15 and the mounting member 23 attached to the roll support frame 12 side. However, the present invention is not limited to this, and any printing pressure measurement sensor may be used as long as the printing pressure for transfer and the printing pressure for retransfer can be measured. The installation location of the printing pressure measurement sensor may be changed as appropriate.

  Furthermore, in the above embodiment, the case where the peripheral speed of the blanket roll 10 and the movement speed v of the plate table 4 and the printing target table 6 are synchronized by controlling the angular speed ω of the blanket roll 10 has been described. However, the moving speed v of the plate table 4 and the printing target table 6 is controlled, or both the angular velocity ω of the blanket roll 10 and the moving speed v of the plate table 4 and the printing target table 6 are both controlled. You may make it control.

  Further, in the above embodiment, after applying a predetermined transfer printing pressure or retransfer printing pressure to the plate 3 or the printing object 5 from the blanket roll 10, the height position Za of the rotation center O of the blanket roll 10 is made constant. Although it has been described that the transfer process and the retransfer process are performed in the state, the transfer printing pressure and the retransfer printing pressure may be controlled to be constant during the transfer process and the retransfer process. In this case, when it is necessary to change the up-and-down movement amount z by the controller 18 during the transfer process and the re-transfer process in accordance with the control of each printing pressure, the above-mentioned corresponding to the change. According to the change of the synchronizing radius R of the blanket roll 10, the synchronizing peripheral speed of the blanket roll 10 determined by the product of the synchronizing radius R and the angular velocity ω of the blanket roll 10 is the movement of the plate 3 and the printing object 3. What is necessary is just to control the angular velocity (omega) of the said blanket roll 10 so that it may synchronize with a velocity.

  Furthermore, in the above-described embodiment, the controller 18 stores the blanket roll retracted height position set at a certain height position as the reference height position H, and the blanket roll is based on the reference height position H. 10 is a vertical distance between the height position Za of the rotation center O and the upper surface height position Zb of the plate 3 held on the plate table 4 and the printing target 5 held on the printing target table 6. The case where the radius R for synchronization of the blanket roll 10 is obtained has been described, but the height position Za of the rotation center O of the blanket roll 10 and the plate 3 held on the plate table 4 and the printing target table 6 are held. If the synchronization radius R as a vertical distance from the upper surface height position Zb of the printing target 5 can be obtained, for example, the above-mentioned each tape in the roll support frame 12 is obtained. In the required position on the side of the frame 12 facing the upstream side of the table running direction a during printing of the plates 4 and 6, on the upper surface of the plate 3 held on the plate table 4 passing below and on the printing target table 6 A laser sensor is provided as a distance sensor for measuring the distance to the upper surface of the printing object 5 held, and the rotation center O of the blanket roll 10 and the plate at the blanket roll retracted height position measured by the laser sensor. The vertical control distance between the upper surface of the plate 3 held on the table 4 and the upper surface height position Zb of the printing object 5 held on the printing object table 6 is set as the synchronization radius R of the blanket roll 10 and the above control. It is possible to control the controller 18 so as to input to the device 18, the height position Za of the rotation center O of the blanket roll 10 and Measuring means for measuring the upper surface height position Zb of the printing object 5 held on the printing table 4 and the printing object table 6 held on the printing table 4 and the reference height position are the same as those of the offset printing apparatus. You may change freely according to an apparatus structure.

  In the above embodiment, the controller 18 stores the printing pressure for transfer and the printing pressure for retransfer, and contacts the upper surface of the plate 3 on the plate table 4 or the upper surface of the printing target 5 on the printing target table 6. The blanket roll 10 is urged downward so that the printing pressure or transfer pressure stored in the controller 18 is applied from the blanket roll 10 to the plate 3 or the printing object 5. In this case, the lifting drive motor 28 has been described as being stopped. However, the blanket roll 10 is moved from the state in which the outer peripheral surface of the blanket roll 10 is in contact with the upper surface of the plate 3 and the upper surface of the printing object 5 in advance. The controller controls the ascending / descending distance of the blanket roll 10 corresponding to the blanket collapse allowance Δz required to apply the printing pressure for transfer and the reprinting printing pressure to the plate 3 and the printing object 5. 8, the controller 18 causes the blanket roll 10 to move from the predetermined blanket roll retracted height position to the retreat height position of the blanket roll, and the required On the plate table 4, control is performed to lower the blanket roll 10 by a dimension obtained by adding the lifting distance of the blanket roll 10 corresponding to the blanket crushing margin Δz required for applying the transfer printing pressure and the required retransfer printing pressure. The blanket roll 10 is brought into contact with the upper surface of the plate 3 held on the upper surface of the plate 3 and the upper surface of the printing object 5 held on the printing object table 6, and the blanket roll 10 is urged downward to urge the blanket roll 10. Further, control is performed so as to apply the transfer printing pressure or the retransfer printing pressure to the plate 3 or the printing object 5. Good. In this case, the load cell 33 may be omitted.

  Furthermore, the encoder 14 for detecting the rotation angle of the blanket roll 10 is not attached to the drive motor 13 for rotation, but as shown by a two-dot chain line in FIG. Of 11a and 11b, a configuration may be adopted in which the rotary shaft 11b is connected directly to the rotary shaft 11b opposite to the rotary shaft 11a to which the rotary drive motor 13 is connected via the speed reducer 32. With this configuration, the rotation angle of the blanket roll 10 can be detected without being affected by the backlash of the gear (not shown) in the speed reducer 32 or the deflection of the power transmission system. The peripheral speed of the blanket roll 10 and the moving speed v of the plate table 4 and the printing target table 6 can be synchronized with higher accuracy, and the printing accuracy can be further improved. Similarly, the encoder 16 attached to the lifting drive motor 28 may be directly connected to the lower end portion of each screw shaft 26.

  The inking device 34 may be any type of inking device as long as it can properly ink the plate 3 held on the plate table 4.

  Furthermore, the offset printing method and printing apparatus of the present invention may be applied when performing offset printing on any print target 5 other than the substrate.

  Of course, various modifications can be made without departing from the scope of the present invention.

3rd edition 5 Print target 9 Linear scale (position detector)
10 Blanket roll 14 Encoder (Rotation angle detector)
15 Ball screw mechanism (lifting mechanism)
16 Encoder (lifting distance sensor)
18 Controller

Claims (4)

  After the printing pattern is transferred from the plate to the blanket roll, the outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the plate moving in one direction with the printing pressure from above, and then rotated. The outer peripheral surface of the blanket roll is brought into contact with the upper surface of the printing object moving in one direction from above with reprinting printing pressure so that the printing pattern is retransferred from the blanket roll to the printing object. In the offset printing method, the synchronization radius obtained from the product of the synchronization radius for the plate and the angular velocity of the blanket roll is defined as a synchronization radius for the plate between the upper surface of the plate and the rotation center of the blanket roll. From the time when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the plate to the time when the transfer process is completed, the moving speed of the plate In addition to the synchronization, a space between the upper surface of the printing object and the rotation center of the blanket roll is defined as a synchronizing radius for the printing object, and the product of the synchronizing radius for the printing object and the angular velocity of the blanket roll The required peripheral speed for synchronization is synchronized with the moving speed of the printing object from the time when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the printing object until the end of the retransfer process. Offset printing method.   From the time when the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the plate to the synchronous peripheral speed of the blanket roll, through the transfer process of the printing pattern, until the outer peripheral surface of the blanket roll is separated from the upper surface of the plate, The plate is synchronized with the moving speed, and the outer peripheral surface of the blanket roll is brought into contact with the upper surface of the printing object, and then the outer peripheral surface of the blanket roll is transferred to the upper surface of the printing object through retransfer of the printing pattern. The offset printing method according to claim 1, wherein the printing is synchronized with the moving speed of the printing object until the printing is separated.   After transferring the printing pattern from the plate to the blanket roll by bringing the outer peripheral surface of the rotated blanket roll into contact with the printing drive pressure from above by the lifting drive mechanism on the upper surface of the plate moving in one direction The outer peripheral surface of the rotated blanket roll is brought into contact with the upper surface of the printing object moved in the one direction by the lifting drive mechanism from above with the retransfer printing pressure, and the printing pattern is transferred from the blanket roll to the printing object. An offset printing apparatus capable of performing a retransfer process, comprising: a rotation angle detector that measures a rotation angle of the blanket roll; and a position detector that detects a moving position of the plate and the printing object. In addition, a synchronization radius for the plate between the upper surface of the plate and the rotation center of the blanket roll, and the rotation angle detector. Obtaining the peripheral speed for synchronization from the product of the angular velocity of the blanket roll obtained based on the measured rotation angle, and the movement speed of the plate obtained based on the synchronous peripheral speed and the detection signal of the position detector The angular velocity of the blanket roll determined based on the function of synchronizing the rotation, the radius for synchronization between the upper surface of the printing object and the rotation center of the blanket roll, and the rotation angle measured by the rotation angle detector And a controller having a function to synchronize the peripheral speed for synchronization from the product of the two and the synchronization peripheral speed and the moving speed of the print target determined based on the detection signal of the position detector. An offset printing apparatus having the configuration described above.   An elevating distance sensor for measuring the elevating distance of the blanket roll by the elevating drive mechanism is provided, and each controller radius is set in the controller, the rotation center of the blanket roll at the blanket roll retracted height position, the upper surface of the plate, and the printing target. The offset printing apparatus according to claim 3, further comprising a function for obtaining the distance based on a distance between the upper surface and an elevation distance measured by the elevation distance sensor.

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